The Disneyland measles outbreak has forced a reckoning on the politics of vaccination: Likely GOP presidential candidates are stumbling over the issue, President Barack Obama has forcefully weighed in, and several states are pushing to make it harder to exempt children from vaccinations.

On Monday, New Jersey Gov. Chris Christie had to backpedal on the question of parental choice in vaccinations. Kentucky Sen. Rand Paul drew fire for connecting vaccines to mental disorders.

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Late Monday night Hillary Clinton chimed in with a pro-vaccine message on Twitter: “The science is clear: The earth is round, the sky is blue, and #vaccineswork. Let’s protect all our kids. #GrandmothersKnowBest”

But as national Republicans try to walk a line between standing up for public health and avoiding government mandates for child vaccinations, state lawmakers are pushing bills that might start to reset stagnant or even falling immunization rates in many parts of the country.

In California and Arizona, two states hit hardest by the current eruption of measles, lawmakers are introducing measures that would make schools’ immunization rates public. Doing so would let parents know the percentage of unvaccinated students on a campus and then consider their own child’s possible risk.

Two bills are in the pipeline in Maine, which last summer saw more than 200 children sickened by whooping cough, to make opting out more difficult by making a parent first consult a primary care doctor, nurse or physician assistant.

On Thursday, Minnesota lawmakers introduced legislation with the same goal. It would require a signature from a health care provider and renewal as a child enters the seventh grade.

The issue is drawing congressional attention, too, with hearings this week and next suddenly focusing on overall vaccine effectiveness, and with Democrats on the House Energy and Commerce Committee asking Chairman Fred Upton to look specifically at the Disneyland outbreak and its spread.

While leading public health and pediatric organizations express optimism that the outbreak could prove a true turning point, they‘re also realistic.

“I think we’re all hoping that this … will encourage people, particularly policymakers, to strengthen their vaccine laws and not weaken them and look very carefully at any exemptions they go to approve,” said physician Georges Benjamin, who leads the American Public Health Association. Even so, he added, “there is no reason to believe it will be different.”

Yet state lawmakers elsewhere are still proposing to make a child’s opt-out easier — with the same muted expectations. Despite given all the publicity and high-profile, celebrity-heightened exposure the “anti-vax” movement has generated, its cause hasn’t translated recently into any legislative victories.

“This is an issue that affects a minority population” of parents, said Dawn Richardson, director of advocacy at the National Vaccine Information Center, which pushes for more parental choice. “Like any minority issue, it’s a challenge to be heard.”

As of Friday, the Centers for Disease Control and Prevention tallied 102 measles cases in 14 states, most of them linked to the initial exposure at Disneyland. That count now crisscrosses the country, from up and down the West Coast to as far away as New York and Pennsylvania. And it’s highly likely the numbers will continue to grow.

“This virus is incredibly contagious,” Sandra Hassink, president of the American Academy of Pediatrics, noted in a statement that emphasized the serious, even life-threatening complications that can result from infection. “When measles was more common in the U.S., hundreds of children died from this virus every year.”

Obama is backing the health experts, calling the science on the safety of vaccinations “pretty indisputable.”

”There is every reason to get vaccinated, but there aren’t reasons to not,” Obama told Savannah Guthrie on the “Today” show.

Yet 2016 Republican hopefuls Christie and Paul said parents should have latitude — with Paul telling talk radio host Laura Ingraham on Monday that “for the most part vaccines should be voluntary.” The eye doctor then went on CNBC and said he had “heard of many tragic cases of walking, talking normal children who wound up with profound mental disorders after vaccines.” He didn’t mention that the study typically cited as evidence of a link was long ago debunked, labeled as fraudulent research by the British medical journal that had published it.

Christie was mild by contrast, saying the government must “balance” public health and parental choice. But a spokesman still sought to clarify his point afterward: “The governor believes vaccines are an important public health protection and with a disease like measles there is no question kids should be vaccinated.”

California and 18 other states allow parents to cite philosophical or personal beliefs, in addition to religious or medical exemptions, as their reason for not having a child immunized. Those conscientious objections cover more than half the population of U.S. school-age children, according to the National Vaccine Information Center.

Richardson said there’s a misperception about many parents who choose to opt out of vaccines. “All it takes is being off schedule for one vaccine, and you need an exemption,” she said. Some parents want to wait until children are older before being immunized against some infectious diseases, she continued, while others may want an exemption for one specific shot but not the whole roster of school-enrollment requirements.

A couple of the proposed measures to curb exemptions were in the works before the first red-splotched child was linked to exposure at Disneyland — but as the count rises, it’s increasing lawmakers’ sense of urgency.

“It’s just very timely,” said Diane Peterson, who tracks state policy for the Immunization Action Coalition.

The bills will follow recent moves in California, Oregon, Washington and Vermont that tightened policies on parents trying to avoid a mandated immunization. In each, parents who want a child exempted must now meet with a medical provider first or review the benefits and risks of vaccines from a state-approved source. Michigan’s state health agency implemented the same language. Early data suggest that some of the policies are decreasing opt-out rates.

Mississippi and West Virginia — the two states with the strictest policies, allowing children to opt out only for medical reasons — actually have legislation to broaden exemptions this session. But their bills seem to be running into obstacles. Three cosponsors of the West Virginia measure removed their names last week. Mississippi’s has yet to come to a committee vote, and the deadline is Tuesday.

Tami Brooks, a Mississippi physician and member of the American Academy of Pediatrics’ committee on state government affairs, suspects the outbreak’s spread has lawmakers there reconsidering. “I definitely think we’ll continue to see states reversing the trend and making it a little more stricter as far as allowing philosophical exemptions or even rescinding some of that legislation,” Brooks said.

Some states have recently added registries to track which students have vaccines. South Carolina took its registry statewide this school year after a one-year pilot.

“Then it’s there for everyone to see — everyone who has reading rights,” said Carolyn Duff, president of the National Association of School Nurses. “It is a leap forward.”

Most of the state exemptions for philosophical or personal beliefs were on the books before the anti-vaccination movement began to have any teeth in the early 2000s. What has changed of late is the number of parents pursuing them. Research shows that the easier it is to get an exemption, the higher the rates will be.

Between 1991 and 2004, the percentage of children nationwide who obtained non-medical exemptions rose from 0.98 percent to 1.49 percent. The increase was even higher in the states with less restricted exemptions, according to the Journal of the American Medical Association.

Exemptions tend to cluster geographically, and that’s what the new bill in California aims to address, said state Sen. Richard Pan, a doctor who successfully sponsored the earlier bill. His new proposal would require a school to inform parents of its vaccination rates as they enroll their child.

“Certainly the outbreak is prompting us to think about, are there additional steps we need to take as well?” Pan said.

Paul Jarris, executive director of the Association of State and Territorial Health Officials, said he is glad to see the outbreak spurring conversation about parents’ responsibility to their communities when it comes to vaccination. “The effort is cumulative, of course, but I think this will be one more effort at strengthening those laws.”

“Measles is bad,” Jarris continued. “It’s more than just a little rash that kids get. I’m hoping that this episode once again demonstrates how we must be vigilant at all times.”